Automatic adjuster for brakes



(No Model l 2 sheets-sheet 1.

E. D. EAM-ES. AUTGMATIG ADJUSTER POR BRAKES.

No. 463,716. Patented Nov. 24, 1891.

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(No Model.) 2 Sheets-Sheet 2.

. E. D. EAMES. AUToMATIe ADJUSTER POR BRAKES.

No. 463,716. Patented Nov. 24, l891.

UNITED "STATES PATENT OEEICE.

ELISHA D. EAMES, OF IVATERTOVN, NEW YORK, ASSIGNOR TO THE CON- SOLIDATED BRAKE-ADJUSTER COMPANY, OF CHICAGO, ILLINOIS.

AUTOMATIC ADJUSTER FOR BRAKES.

SPECIFICATION forming part of Letters Patent No. 463,716, dated November 24, 1891.

Application filed January 25, 1890. Renewed May 6, 1891. Serial No. 391,709. (No model.)

To all whom it may concern/.-

Be it known that I, ELISHA D. EAMES, of lVatertown, in the county of `Jefferson and State of New York, have invented certain Improvements in Automatic Brake-Adjusters, of which the followingl is a specification, reference being had to the accompanying drawings, and to the letters of reference marked thereon.

The object of this invention is to preserve, automatically, the adjustment of the brakeshoes tothe normal or predetermined distance from the wheels intended to exist when brakes are o, so that upon wear of the shoes the increased amount of space between the shoes and the wheels will be at once taken up and the original distance between the shoes and the wheels existing when brakes are off reestablished. Various devices for effecting such a result have been projected, some of which have attained a greater or less degree of success.

My invention consists, broadly, in the enlployment of a threaded, notched, or serrated brake-rod and two jaws, each being provided with one or more half-nuts adapted to engage the threaded or notched rod, and with a thimble or similar device to support it. Each jaw is connected to the brake-lever, and under certain conditions is adapted to be moved forward on the brake-rod by the action of the brake-lever, one jaw securely holding the brake-rod while the other is being moved forward, all of which will be more fully described in the following specification.

In the accompanying drawings, Figure 1 is an elevation of a pair of car-wheels with their brakes and appendages, showing the application thereto of my invention. Fig. 2 is a detached perspective view, upon an enlarged scale, of the parts entering` chiefly in-to my invention. Fig. 3 is a vertical longitudinal section of Fig. 2. Figs. t and 5 are cross-sections of Fig. 2 on the lines a: a: and y y, respectively. Figs. 6, '7, and 8 are modifications. j

Similar letters of reference indicate similarI parts in the respective figures.

A A show parts of the truck-frame, and B B the car-wheels. C C are the brake-beams, suspended by links c to the truck-frame. D

D represent the brake-levers, and E is a brake-rod uniting them. Fis a rod connecting the upper end of the brake-lever D to the diaphragm, piston, winding-staff, or other agentfor the application of power. All of said parts and devices may be of any ordinary or approved construction.

The lower end of the brake-lever D is pivoted to the brake-rod E, the lever carrying the brake-beam C in the ordinary manner. The other brake-lever D', which carries the beam C', is pivoted at g to one end of a jaw G. This jaw consists of two parallel sides bolted together, said two sides being held a suitable distance apart by means of the halfnuts g g2. The end of the rod E extends between the two dies of the jaw G and is threaded or notched to adapt it to engage with the half-nuts g g2, which are opposed to each other. The rod E also passes loosely through a thimble g3, pivoted at g4, within the jaw G,

between the two half-nuts. The point of connection g between the lever D and the jaw G is preferably below the center of the line of draft of the rod E, for a purpose to be hereinafter explained.

H is a rod bifurcated at its rear end for the reception of the lever D', which is connected to it by means of the pin d. Each branch of the rod H is provided with a slot h', through which the pin d passes, allowing the lever D to have a limited movement without affecting the rod I-I, this movement being equal to that normally existing between the shoes and the wheels when brakes are o. The forward end of the rod H is pivotally connected ath to the rear end of a jaw I,

similar in construction to the jaw G, but shorter. This jaw has at its rear end a halfnut t2, adapted to engage the upper threaded portion of the rod E, and at its forward end a thimble t', pivoted to it at t', and through which the rod E loosely passes. The jaw I is also furnished with downwardly-extending lugs t3, curved inwardly toward each other under the rod E and serving to limit the tilting movement of the jaw I when such movement becomes necessary in the operation of the device.

The general operation is as follows, referring particularly to Fig. 3: The distance which roo vent slipping.

the brake-shoes are designed to move in setting the brakes is, as has been stated, the distance which the brake-lever D is free to nieve in the slots 7L without acting on the rod II. It is therefore seen that so long as the brake-shoes (they having been properly adjusted) are unworn the lever D will in the act of setting brakes move `only a distance equal to that provided for by the slots h,and consequently the rod II will not be moved; but wear of the shoes having occurred, in order to bring the shoes up to the wheels a greater movement of the lever D becomes necessary, and this will cause the rod II to be pushed forward, thereby tilting the jaw I on its pivot t" and lifting the half-nut L2 out of engagement with the threaded portion of the rod E, thus permitting the jaw I, thimble c', and half-nut t2 to slide forward on the rod to the extent of the wear. Under these circumstances, when brakes are released the first strain will, in the effort to take up slack, come on the rod II and the half-nut 'i2 and the strain on the half -nuts g g2 be taken off. In practice the rod E is about eight feet in length and somewhat flexible. It is also continually in a condition of tension or strain in the direction of its length by reason of the springs on the brake-beams. New in the act of setting the brakes the point of connection between the brake-beam C and the leverD (designated by is the fulcrum; but in the act of releasing brakes and supposing slack is to be taken up, as before described, x becomes the point at which power is applied and the pin CZ the fnlcruni. Consequently the lever above the pin (Z will move backward and the part below forward. rlhe connection between the leverD and the jaw G, being below the center of the line of draft, will cause the jaw G to swing on its pivotal connection to the thimble g3, tilting the for ward end up and so disengaging the halfnuts g g2 and permitting the jaw G to move forward on the rod E a distance equal to the slack taken up. rlhe strain on the rod H and jaw I will also tend to deflect the center of the rod E, and so assist in throwing the halfnuts g g2 out of engagement. The strain will remain on the rod ll until the next operation of applying brakes. As soon as the lever D begins to move for this purpose will again become the fulcrum, and the lower end of the lever move in a reverse direction, and

for the reason that it is connected to the jaw G below the center of the line of draft its effect on the jaw will be just the reverse of that in the operation of taking up the slack. Thus, instead of tending to throw the halfnuts g g2 out of engagement with the rod E, it will, on the contrary, force and hold them securely in engagement with the rod and pre- The strain will then be transferred from the rod II to the jaw G and remain on it until it becomes necessary to again take up slack.

The construction just described is that when the pin ci becomes the fulcrum and x i the point at which power is applied the lower end of the lever D will move as indicated by dotted lines. This will necessarily cause the jaw G to ,swing on the thimble g3 and so throw the half-nuts out of engagement.

Referring to Fig. 7, the rod E is shown with a ratchet-thread, and only one half-nut having a similar thread is used in the jaw G, the thimble g3 being placed somewhat farther back than in the device illustrated in Fig. Here the connection between the brakeelever and the jaw maybe on the line of draft of` the brake-rod, for the inclined sides of the threads will permit the half-nut to slide forward when necessary, While the vertical sides of the threads on the rod and half-nut, when interlocked, will prevent any movement of the jaw backward on the rod.

In Fig. 8 is shown a block g5, whose upper surface is slightly rounded. This block may be substituted for the thimble g3 to form a support for the brake-rod.

- I have illustrated and described half-nuts as forming the means of engagement lbetween the jaws and the threaded or notched brake-rods, and I prefer to use them, for the.

reason that they present a large surface for engaging the rod, and are thereforeV better adapted to withstand the strain, and, further, are less liable to slip than any device presenting a smaller engaging surface. I do not,

however, limit myself to the use of half-nuts,

as I consider any other mechanical device known to the art and adapted to perform the same function as within the scope of my invention.

Having described my invention, I claim-- l. The combination, in a brake mechanism, of a threaded or notched brake-rod, a jaw, a thimble or other suitable device within said jaw to support the rod, a half-nut within said jaw adapted to engage the threaded rod, and a brake'lever connected to said jaw, substantially as specified.

2. The combination, in a brake mechanism, of a threaded or notched brake-rod, two jaw s, each provided with a device to support the rod and with means to engage the threads or :notches on said rod, and a brake-lever connected to both jaws, substantially as specified.

3. In a brake mechanism, a brake-lever, a threaded or notched brake-rod, and a jaw connecting the lower end of the brake-lever with the threaded rod, substantially as described, combined with a second jaw having a device to engage the threaded rod, and a rod leading from the second jaw and joined to the brake- IOO lIO

lever by a slotted connection, substantially as specified.

leading from the second jaw and joined to the brake-lever by a slotted connection, sub- 4. In a brake mechanism, a brake-lever, a stantially as specified.

threaded or notched brake-rod, a jaw connected to the lower end of the brake-lever, a device Within said jaw to support the rod,

and half-nuts also Within said jaw adapted' to engage the threaded rod, combined with a second jaw provided with similar supporting :o and engaging devices for said rod, and a rod In testimony whereof I have hereunto set my hand and seal.

ELIsHA D. EAMES` [n s.]

Witnesses:

WILFRED EAMES, THOMAS C. CHITTENDEN. 

